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Plant pathogenic bacteria often have a narrow host range, which can vary among different isolates within a population. Here, we investigated the host range of the tomato pathogen Clavibacter michiganensis (Cm). We determined the genome sequences of 40 tomato Cm isolates and screened them for pathogenicity on tomato and eggplant. Our screen revealed that out of the tested isolates, five were unable to cause disease on any of the hosts, 33 were exclusively pathogenic on tomato, and two were capable of infecting both tomato and eggplant. Through comparative genomic analyses, we identified that the five non-pathogenic isolates lacked the chp/tomA pathogenicity island, which has previously been associated with virulence in tomato. In addition, we found that the two eggplant-pathogenic isolates encode a unique allelic variant of the putative serine hydrolase chpG (chpGC), an effector that is recognized in eggplant. Introduction of chpGC into a chpG inactivation mutant in the eggplant-non-pathogenic strain Cm101, failed to complement the mutant, which retained its ability to cause disease in eggplant and failed to elicit hypersensitive response (HR). Conversely, introduction of the chpG variant from Cm101 into an eggplant pathogenic Cm isolate (C48), eliminated its pathogenicity on eggplant, and enabled C48 to elicit HR. Our study demonstrates that allelic variation in the chpG effector gene is a key determinant of host range plasticity within Cm populations.

The hepatocytes within the liver present an immense capacity to adapt to changes in nutrient availability. Here, by using high resolution volume electron microscopy, we map how hepatic subcellular spatial organization is regulated during nutritional fluctuations and as a function of liver zonation. We identify that fasting leads to remodeling of endoplasmic reticulum (ER) architecture in hepatocytes, characterized by the induction of single rough ER sheet around the mitochondria, which becomes larger and flatter. These alterations are enriched in periportal and mid-lobular hepatocytes but not in pericentral hepatocytes. Gain- and loss-of-function in vivo models demonstrate that the Ribosome receptor binding protein1 (RRBP1) is required to enable fasting-induced ER sheet-mitochondria interactions and to regulate hepatic fatty acid oxidation. Endogenous RRBP1 is enriched around periportal and mid-lobular regions of the liver. In obesity, ER-mitochondria interactions are distinct and fasting fails to induce rough ER sheet-mitochondrion interactions. These findings illustrate the importance of a regulated molecular architecture for hepatocyte metabolic flexibility.

Abstract Objective With altered sense of taste being a common symptom of coronavirus disease 2019 (COVID-19), the main objective was to investigate the presence and distribution of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) within the tongue over the course of infection. Methods Golden Syrian hamsters were inoculated intranasally with SARS-CoV-2 and tongues were collected at 2, 3, 5, 8, 17, 21, 35, and 42 days post-infection (dpi) for analysis. In order to test for gross changes in the tongue, the papillae of the tongue were counted. Paraffin-embedded thin sections of the tongues were labeled for the presence of SARS-CoV-2 antigen. Results There was no difference in fungiform or filiform papillae density throughout the course of infection. SARS-CoV-2 antigen was observed in the vallate papillae taste buds (3–35 dpi) and autonomic ganglia (5–35 dpi), as well as in the serous and mucous salivary glands of the posterior tongue (2–42 dpi). Conclusion The presence and distribution of SARS-CoV-2 suggest that the virus could cause taste disturbance by infecting the vallate papillae taste buds. This effect could be exacerbated by a diminished secretion of saliva caused by infection of the serous salivary glands and the autonomic ganglia which innervate them.

The COVID-19 pandemic devastated many communities and exacerbated existing inequities, particularly for Mexican American communities along the South Texas border. During this tumultuous time, many Mexican American college students balanced coursework, work, and familial responsibilities in the Rio Grande Valley (RGV), a Texas borderland region disproportionately affected by the spread of COVID-19 when compared to Texas overall. This qualitative study uses narrative analysis to examine oral history interviews of 11 college students from the RGV to understand how COVID-19 shaped their experiences throughout the 2020-2021 academic year and how they leveraged region-specific cultural assets to navigate their multiple roles during this historic time. The authors draw from Borderland Cultural Wealth (Yamamura et al., 2010) to posit a college retention framework by examining how 11 college students navigated the COVID-19 pandemic to inform policy and practices. Findings suggest that Mexican American students leveraged their RGV cultural assets to navigate health disparities, secure income for themselves and their families, and prioritize familial responsibilities while completing virtual coursework during the pandemic. This study contributes to the research that challenges RGV student deficits and illuminates the importance of cultural assets of Mexican American communities in the RGV. We provide future research recommendations and considerations for asset-based college retention policies and practices in higher education.

This study examined the perceived benefits and challenges of using synchronous videoconferencing as a tool to teach academic content and engage United States (U.S.) elementary students in intercultural exchanges with peers in other countries. The study employed a sequential mixed-methods design that consisted of first surveying, then interviewing participants. The findings suggested that synchronous videoconferencing served as an effective tool to simultaneously promote students' learning of existing curricula all while amplifying the students' understanding of diverse cultures throughout the world. Furthermore, participants noted only a few minor challenges, such as scheduling issues and/or technical difficulties. Overall, participants highly recommended the integration of synchronous video interactions as a tool to help enhance lessons, promote long term retention of content, and facilitate intercultural exchanges among students.

Mathematical word problems present various challenges for students, including English learners. Research on word problem-solving interventions for elementary English learners with or at risk for mathematics disabilities/difficulties was reviewed. A systematic search of studies conducted between 2012 and 2022 yielded a total of 14 research studies that met all of the preestablished criteria. Results of this review indicate that more than half of the studies implemented interventions with a focus on text comprehension. Implications and directions for future research and practice are presented.

ES. El objetivo de este artículo de corte conceptual es establecer un vínculo entre las perspectivas de mediatización, desintermediación y cierre social con la intención de teorizar las estrategias de monopolización de la información desarrolladas por el populismo contemporáneo. Tomando al gobierno de México encabezado por Andrés Manuel López Obrador como referente empírico, se plantea que el populismo no se limita a intentar excluir del proceso de comunicación a la institución y práctica del periodismo (desintermediación), sino que da un paso más al intentar usurpar sus funciones de establecimiento de agenda, verificación de la información y trabajo de campo. Para conceptualizar la relación entre los procesos de mediatización, desintermediación y usurpación, los referentes empíricos de este artículo son: (1) las conferencias de prensa de López Obrador, que procuran establecer la agenda en lugar del periodismo, (2) su sección de verificación de noticias gubernamental, “¿Quién es quién en las mentiras de la semana?”, que socava la credibilidad de la prensa y busca suceder a la verificación de noticias periodística, y (3) el proyecto fallido de la “Red de Comunicadores del Pueblo”, que pretendía reemplazar el trabajo de campo periodístico, mediante una red de periodistas ciudadanos partidarios. Entre los resultados de este trabajo destaca que la eliminación de la mediación periodística impide la rendición de cuentas y permite que los políticos califiquen como “ataques” los cuestionamientos desde el periodismo. Los procesos aquí analizados derivan en una usurpación de las funciones que le corresponden a la prensa en una sociedad democrática para suplirlas por prácticas que simulan ser periodísticas no obstante su ausencia de rigor y propensión a reproducir el discurso gubernamental. Asimismo, se ampara la desinformación en tanto se facilita la circulación de información que no ha sido contrastada o verificada y se incrementa la vulnerabilidad de la práctica del periodismo en México. *** PT. O objetivo deste artigo de cunho conceitual é estabelecer uma relação entre as perspectivas de midiatização, desintermediação e fechamento social, com a intenção de teorizar as estratégias de monopolização da informação desenvolvidas pelo populismo contemporâneo. Tomando como referência empírica o governo do México liderado por Andrés Manuel López Obrador, argumenta-se que o populismo não se limita a tentar excluir do processo de comunicação a instituição e a prática do jornalismo (desintermediação), mas dá um passo além ao procurar usurpar suas funções de definição de agenda, verificação das informações e trabalho de campo. Para conceituar a relação entre os processos de midiatização, desintermediação e usurpação, as referências empíricas deste artigo são: (1) as coletivas de imprensa de López Obrador, que buscam definir a agenda no lugar do jornalismo; (2) sua seção governamental de verificação de notícias, “Quem é quem nas mentiras da semana?”, que mina a credibilidade da imprensa e procura ocupar o lugar da verificação jornalística de notícias; e (3) o fracassado projeto da “Rede de Comunicadores do Povo”, que pretendia substituir o trabalho de campo jornalístico por meio de uma rede de jornalistas cidadãos partidários. Entre os resultados deste trabalho destaca-se que a eliminação da mediação jornalística impede a prestação de contas e permite que os políticos qualifiquem os questionamentos feitos pelo jornalismo como “ataques”. Os processos aqui analisados conduzem a uma usurpação das funções que correspondem à imprensa em uma sociedade democrática, substituindo-as por práticas que simulam ser jornalísticas apesar de sua falta de rigor e propensão a reproduzir o discurso governamental. Da mesma forma, a desinformação é amparada na medida em que facilita a circulação de informações que não foram checadas ou verificadas, aumentando a vulnerabilidade da prática do jornalismo no México. *** EN. The objective of this conceptual article is to establish a relationship between mediatization, disintermediation and social closure, with the intent of theorizing the strategies of information monopolization developed by contemporary populism. The Mexican government, led by Andrés Manuel López Obrador, is our empirical reference, and we argue that populism is not limited to trying to exclude the institution and practice of journalism from the communication process (disintermediation); it goes even further by seeking to usurp its functions of agenda-setting, information verification and fieldwork. In order to conceptualize the relationship between mediatization, disintermediation and usurpation, we used the following empirical references: (1) López Obrador’s press conferences, which seek to set the agenda rather than journalism; (2) his government fact-checking section, “Who’s Who in the Lies of the Week?”, which undermines the credibility of the press and seeks to do away with journalistic fact-checking; and (3) the failed “People’s Communicators Network” project, which sought to replace journalistic fieldwork with a network of partisan citizen journalists. One particular result from this work worth highlighting is that eliminating journalistic mediation hinders accountability and allows politicians to label questions raised by journalism as “attacks”. The processes analyzed in this paper lead to the usurpation of the press in a democratic society, replacing their functions with others that appear to be journalistic but lack the rigor and propensity to reproduce government discourse. Similarly, disinformation is supported to the extent that it facilitates the circulation of unchecked and/or unverified information, thus increasing the vulnerability of journalism in Mexico. *** FR.L’objectif de cet article de nature conceptuelle est d’établir un lien entre les approches de médiatisation, de désintermédiation et de fermeture sociale, afin de théoriser les stratégies de monopolisation de l’information développées par le populisme contemporain. En prenant pour référence empirique le gouvernement mexicain d’Andrés Manuel López Obrador, nous avançons que le populisme ne se limite pas à tenter d’exclure l’institution et la pratique du journalisme du processus de communication (désintermédiation), mais va plus loin, puisqu’il cherche à usurper leurs fonctions de définition de l’agenda, de vérification de l’information et de travail sur le terrain. Pour conceptualiser la relation entre les processus de médiatisation, de désintermédiation et d’usurpation, le corpus empirique comprend : (1) les conférences de presse de López Obrador, qui s’attachent à définir un agenda à la place du journalisme, (2) sa séance gouvernementale de vérification des informations, le « Qui est qui dans les mensonges de la semaine ? », qui sape la crédibilité de la presse et cherche à se substituer à la vérification journalistique des faits, et (3) le projet avorté de « Réseau de communicateurs du peuple », qui visait à remplacer le travail journalistique sur le terrain au moyen d’un réseau de journalistes citoyens partisans. Notre étude montre notamment que l’élimination de la médiation journalistique entrave la redevabilité et permet aux hommes politiques de qualifier d’« attaques » les questions posées par les journalistes. Les processus analysés ici entrainent une usurpation des fonctions qui reviennent à la presse dans une société démocratique, en les remplaçant par des pratiques prétendument journalistiques, malgré leur manque de rigueur et leur propension à reproduire le discours gouvernemental. De même, la désinformation est encouragée dans la mesure où l’on facilite la circulation d’informations qui n’ont pas été recoupées ou vérifiées, ce qui accroît la vulnérabilité de la pratique du journalisme au Mexique. ***

Trypanosoma vivax displays distinct mitochondrial genomes: intact in Africa and degraded in South America. This finding, formerly reported from four isolates, suggested an association between mitochondrial mutations and adaptation to exclusive mechanical transmission outside Africa, circumventing mitochondrial activity essential for cyclical transmission by tsetse flies. Here, we characterized the mitochondrial ND7 and COIII genes in 25 South American isolates of T. vivax from livestock from Argentina, Brazil, Colombia, Ecuador, and Venezuela, as well as in 11 African isolates from Mozambique, Ethiopia, Uganda, Nigeria, and Burkina Faso from tsetse flies, antelopes, and cattle. Phylogenetic inference supported the lineages TVV (Trypanosoma vivax vivax) and TVL (Trypanosoma vivax-like), predominant in South America/West Africa and East Africa, respectively. Both ND7 and COIII genes were intact in all African TVV and TVL isolates and, for the first time, in 10 South American isolates from Brazil. Remaining South American isolates exhibited some degree of gene erosion, including ~142 bp deletion at the 3′ end of ND7 disclosed in Venezuela and Colombia, ~163 bp deletion at the 3′ end of ND7 in Brazil and Argentina, and ~750 bp deletion from the 5′ end of ND7 to the 3′ end of COIII in Venezuela. Comprehensive analyses of whole mitochondrial genomes from additional South American and African isolates are crucial for formulating reliable hypotheses regarding the origin, absence, and rapid mitochondrial degradation observed in South American T. vivax.

En este artículo abordamos la narración Paso del norte, que forma parte del libro El llano en llamas (1953), del escritor mexicano Juan Rulfo (1917-1986). El relato aglutina la experiencia descarnada del tránsito humano desde tierras mexicanas hacia Estados Unidos. La propuesta conceptual de la trashumancia se pone al servicio de interpretar esta experiencia liminar de tránsito y desarraigo de la tierra que nos ve nacer hacia donde se anhela llegar. El concepto de trashumancia originado en su etimología latina trans-humus (cruce de tierras) se inscribe en la propuesta teórica de la “hospitalidad-trashumancia”. De ese modo, puede emplearse como una herramienta epistemológica que responda con mayor precisión a la experiencia social contemporánea donde se mezclan la pobreza extrema y los desplazamientos forzosos.

This investigation focused on identifying deforested areas, tracking land use changes, and performing temporal analysis through thematic mapping in La Concordia canton, located in northwestern Ecuador. Utilizing NDVI analysis of Sentinel-2 L2A images from 2019, 2022, and 2023, the study assessed vegetation health and cover. NDVI values were categorized into land cover classes to calculate deforestation rates. The analysis reveals significant changes in La Concordia's vegetation, characterized by a decline in healthy vegetation and an increase in bare soil areas from 2019 to 2023, alongside a concerning deforestation rate of -3.89% over the same period. These findings underscore the urgent need for sustainable land management practices to address the impacts of agricultural expansion and intensification on the region’s ecosystem.